General methods of test for pigments and extenders - Part 9: Determination of pH value of an aqueous suspension (ISO 787-9:1981); German version EN ISO 787-9:1995— 4 стр.
Extenders for paints - Specifications and methods of test - Part 19: Precipitated silica (ISO 3262-19:2000); German version EN ISO 3262-19:2000— 13 стр.